/* eslint-disable no-extra-semi */
;(function(window, document) {
	var hearts = []
	window.requestAnimationFrame = (function() {
		return (
			window.requestAnimationFrame ||
			window.webkitRequestAnimationFrame ||
			window.mozRequestAnimationFrame ||
			window.oRequestAnimationFrame ||
			window.msRequestAnimationFrame ||
			function(callback) {
				setTimeout(callback, 1000 / 60)
			}
		)
	})()
	init()
	function init() {
		css(
			".heart{width: 10px;height: 10px;position: fixed;background: #f00;transform: rotate(45deg);-webkit-transform: rotate(45deg);-moz-transform: rotate(45deg);}.heart:after,.heart:before{content: '';width: inherit;height: inherit;background: inherit;border-radius: 50%;-webkit-border-radius: 50%;-moz-border-radius: 50%;position: absolute;}.heart:after{top: -5px;}.heart:before{left: -5px;}"
		)
		attachEvent()
		gameloop()
	}
	function gameloop() {
		for (var i = 0; i < hearts.length; i++) {
			if (hearts[i].alpha <= 0) {
				document.body.removeChild(hearts[i].el)
				hearts.splice(i, 1)
				continue
			}
			hearts[i].y--
			hearts[i].scale += 0.004
			hearts[i].alpha -= 0.013
			hearts[i].el.style.cssText =
				'left:' +
				hearts[i].x +
				'px;top:' +
				hearts[i].y +
				'px;opacity:' +
				hearts[i].alpha +
				';transform:scale(' +
				hearts[i].scale +
				',' +
				hearts[i].scale +
				') rotate(45deg);background:' +
				hearts[i].color
		}
		requestAnimationFrame(gameloop)
	}
	function attachEvent() {
		var old = typeof window.onclick === 'function' && window.onclick
		window.onclick = function(event) {
			old && old()
			createHeart(event)
		}
	}
	function createHeart(event) {
		var d = document.createElement('div')
		d.className = 'heart'
		hearts.push({
			el: d,
			x: event.clientX - 5,
			y: event.clientY - 5,
			scale: 1,
			alpha: 1,
			color: randomColor(),
		})
		document.body.appendChild(d)
	}
	function css(css) {
		var style = document.createElement('style')
		style.type = 'text/css'
		try {
			style.appendChild(document.createTextNode(css))
		} catch (ex) {
			style.styleSheet.cssText = css
		}
		document.getElementsByTagName('head')[0].appendChild(style)
	}
	function randomColor() {
		return (
			'rgb(' +
			~~(Math.random() * 255) +
			',' +
			~~(Math.random() * 255) +
			',' +
			~~(Math.random() * 255) +
			')'
		)
	}
})(window, document)
